Road construction.



C. Bi CHATHELD.

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CHARLES B. CHATFIELD, OF GRAND RAPIDS` MICHIGAN.

ROAD CONSTRUCTION.

Specification of Letters Patent.

Patented June 18, 1918.

Application tiled April 7, 1917. Serial No. 160,405.

To all whom. t may concern Be it known that I, (ln/ienne B. CHAT- FIELD, a citizen of the United States of America, and resident of Grand Rapids, county of Kent., and State of Michigan. Vhave invented certain new and useful Improvements in and Relating to Road Construction, of which the following,r is a specification.

The invention relates to certain improve ments in roadways and in the method otl con- :structingr the saine; and the objects and nature of the invention will bc readily understood by those skilled in the art in the light. of the following explanation ot' the accom panying drawingey illustrating what l now believe Yto be the preferred embodiments of my invention from among other forn'uitioue, arrangements and constructions within the Spirit and scope of the invention.

The present` invention relatesv to the con struction of concrete, or other long wearing material, roads, and is particularly directed to roads formed with a narrow single track concrete portion, that is, to roadS which are formed of u width to accommodate the average four wheeled vehicle. Roads of this narrow width are usually laid through die`- tricts where the number of vehicles passingr over the roadl is small and it therefore unnecessary to construct a wide road which will acconnnodate more than a single vehicle, as the number ot' vehicles met on the road which will require turning out in passing is comparatively small. The expense of construction and maintenance is therefore considerably reduced by constructing these singletrack concrete roads.

The fundamental and primary defect and disadvantage in the usual construction of narrow roads of the type referred to and in other constructions in which a material is added to the road proper, has been the formation of rute or depressions due to the lueahing down and separating of the road and the material lying along, either side tlu reof, whereby the abutting edges of the road and the adjacent material seperate and assumeJliflorent levels. When vehicles turn from the road onto the portions on each side it is often exceedingly difficult. to regain the road, aa the wheels of the vehicle must sur mount these ruts or depressione so formed, and in turning from and returning t0 the road the vehicle is subjected to severe jolts and shocks as the wheels encounter the rough and uneven formation along the edges of the road proper.

It is an object. of the present invention to" construct a road with adjacent lateral portions, whereby the breaking down and `aepavration between the road and these lateral portions, which results in the formation of ruta und depressions, is overcome and a roadway is formed which presenta an even unbroken surface.

It is a further object of the invention to proudtl means whereby adjacent portions may be added to a hard long wearing material road und be hound thereto al. `the adju-- cent edges so that an even unbroken .surface is presented by the road and the adjacent portions.'

,It is a further object` of the invention to provide an improved method of constructing rondeI of the type provided with lateral portions.

lt io a further object of the invention to construct a roadway in which the cost. of constliu'lion and muint'cnamfe is low and the disadvantages and defects of prevailing con strut-tions and methods are eliminated.

The invention consists in certain novel features in construction and in combinations` und arrainrel'nents as more fully and particularly specified hereinafter. t

Referring to the accompanyiup,r dra wings:

Figure 1, is a vertical trans-terse section through a portion of a road during the Fig. ,2, is a vertical transverse section through a completed roadway constructed in accordance with my invention. f

Fig, 3, is a `vertical Section through a modified form of construction.

ln the accompanying drawing l have disclosed a roadway offtlie 'type formed of a narrow single tracltatgpncrete portion provided on each side with parallel adjoining laiteral, side or shoulder portions formed of granular material, such as gravel or tn acadaln. I do not wish however, to limit the use of lny invention to such a construction as it is clear thutfit is adapted, as before pointed out, to constructing lateral or shoulder portions to any Width, formation, or arrangement of road. For the purposes of elearness and as an example of the use to' which my invention may be put, I have disclosed this type of road construction herein.

In the particular example illustrated, the roadway is formed of a single track concrete portion having adjoining side, shoulder or lateral iortions on each sido thereof, preferably iormed of gravel or macadam, and joined to and connected with the con-crete portion along their contacting or abutting edges by a viscous bindin medium. The shoulder or laterall grave portions, thus bound at their edges to the adjacent edges of the narrow concrete portion, are, constructed of approximately equal depth or thickness with the concrete portion at their alo bound edges and gradually lessen in 'depth outwardly and upwardly to their outer edges, at which point they are preferably of no appreciable depth or thickness.

The central single track concrete portion is formed of a series of base orlbed plates ot' concrete and upon these plates a wearing surface. is formed of the desired thickness of a rich mixture. Between these concrete bed plates a space is left. to provide the usual ey pansion joints. The wearing surfaces or to'p layer of concrete are treated to present a Toughened finish to overcome slipping or skiddiug of vehicles thereon and to assist the Wheels thereof in obtaining a hold or grip on the road surface.

In the drawings, I show the sub-base E, formed of einders, gravel or sand, or a mixture thereof, forming the sub-grade upon which the roadway ofniy invention is constructed. This sub-base E is laid to form a sub-grade having its maximum depth at its central 1portion and slopingr outwardly and upward y to the ground level to form bases for the side, shoulder or lateral portions of the roadway. Upon the central portion o1 the sub-grade I form a series of concrete or equivalent material plates D which are separated by the usual expansion joint. Upon each plate D a layer of concrete (or equivalent material) A is provided to forni a wearing surface. The concrete wearing surface or top layer A is preferably formed of a rich concrete mixture, for` example., 40% cement, crushed granite or quartzite, and 10% clean sharp sand, and this mixture is formed to make a plastic material whiclrmay be readily worked with a trowel or the like instrument.

On both sides of the concrete portions A, D, and upon the upwardly and outwardly extendin surfaces of the sub-base E, gravel or maca am is'laitl with the upper surfaces approximately flush ror level with the upper surface of the concrete layer A, at least at the lines of joindure with the concrete layer A. A viscous binding element C connects or binds the abutting edges of .the granulai` sides, shoulders or laterale B and the narrow concrete road A, D, and prevents the laterale B from separatin from the concrete road and forming ruts, Ldepres` sions, or other objectionable unevenness or roughness between the concrete portion and the ravel laterale. y

T iis binding element C may consist of a mixture of a material consisting of conn paratively smell articles such as crushed stone, 4and a viscous substance, as tar, or the like. This mixture provides a, mass which is interposed between the adjacent edges of the single track concrete body and the shoulN der or lateral portions and permeates or extends and works a distance into the grana lar masses forming the lateral portions ad jacent the road proper, thus binding 'the lateral portions to the road and forming a construction which prevents` tbc lateral portions from separating or breaking down with respect to the road. ln place of a binding element composed oi tbc mixture above referred to, a viscous substance alom. may be used, When using a wist-ous sub Stance, such ns tar or the like, as thrbinding` element, the same will be interposed between the adjacent edges of the road proper and the laterale and will permeate and i'ill the in terstices between the particles forn'iin`5 the laterale and thus create a mass or formation at the edge portion of each lateral adjoiningY thesingle track concrete body which will bind the lateralsto the same and prevent breaking down or separation therefrom.

In constructing a roadway according to the present invention, the concrete portion A D is first laid on the sub-baso E and prei'- erably between opposite parallel forms l, composed of strips of wood, or other mateA rial, which are held in elevated position by stakes or pegs 2. The strips l are main-- tained a distance above the subgrade .lil se that there is a space between the sub-grmley and the strips and the opposite strips are an ranged a distance apart equal to the width ot the central or concrete portion of the road to be produced. The concrete bed or base plates D are formed between strips 1 and the concrete when being laid is tamped or forced so that portions thereof will How outwardly beneath the forms 1 and extend laterally a distance beyond the same. In this manner the concrete portion is formed. with the extensions or flanges D along its lower edges. After the bed or base plates are laid the top layer of rich concrete mixture A is laid between the forms l on the plates D and level with the tops of the forms 1. The upper surface .of the layer A is then broomed or suitably treated to remove a portion of the material and leave the stone partielesin the mixture partly exposed and protruding in order to roughen the wearing surface as at F, and revent vehicle wheel tires slipping or skiddlng thereon. This arrangement and construction of the concrete roadway is my preferred form but it is not `essential that the Concrete portion be construeted of the two grades or layers of con crete. It may be formed of the material of the base plates throughout or of any other desired material. The top or wearing surlare A is proviifled topresent a smoother road suriee and one which prevents undue slipping` or skidding of vehicle wheel tires thereon.

After the concrete portions A D are set, the forms 1 and stakes 2 are removed. The sub grades on both sides of the concrete are then filled in with the material to form the. latex-als. These laterals or shoulders are constructed with their` upper surfaces approximately flush or level with the surface F of the road proper. After the lateral porH tions are laid and leveled or graded the desired hindin element is introduced between the adjacent edges of the laterals and the road proper. As before explained, the binding element may consist of any sah- Stanee or mixture ot a viscous nature which will enter into the masses of the granular lengths of the roadway and approximately into the opposite edges of the concrete length thereof to protect the edges of the concrete length and at each edge thereof form a mass which is of suliicieint body to Stand up or resist strains and stresses applied thereto and which prevents, due to its somewhat elastic or resilient nature, any separation or breaking down between the granular portions o1V the road and the intervening ooncrete body thereof. The essential characteristie ot the inventic'm is the introduction of a binding element between the edge of the eonerele or permanent length of the road Way and the adjarent portion of a parallel adjoining granular length of the roadway for the purpose ot' protecting the edge of the concrete length and joining the granular length thereto against breaking down along' the joint. In the particular example illusie trated, the extensions or flanges D formed at the lowel' edges of the concrete plates, project under the adjacent portions olii' the gravel or macadam and form seats or supports which tend to more firmly mainlain the gravel, binding element, and concrete in position. The 'formation of these extensions or flanges is not however, essential to m invention but merely adds to the strength ofythe particular construction, and do not, Wislrto limit my invention to the use of such construction, as it is evident the road proper may be formed with straight side or edge portions. i

In forming the lateral portions the material of which' they are constructed, may be lessened or decreased in size or diameter of particles at the portion thereof adjacent the road proper, so that when the binding element is introduced a more compact solid construction will result adjacent the edges oi' the road.

After the concrete and the, laterals are in place upon the sub-base and are firmly and tightly settled and packed thereon: a. suitable binder such as hot. tar. asphaltuin, or the like, may be poured upon the laterals adjacent. the edges oi the concrete to prevent the adjacent upper edges of the joined mate` rial from breaking!` down or separating'.

In Fig. 3, of the drawings, a modified form of road construction is shown in which the space left by the removal of the forms is filled with a strip of bituminous concrete G. In this forni the edges of the abuttiner materials are all provided with a suitable binder preventing breaking down and separation thereof. This strip ol bituminous concrete could be rolled into this space or inlrrnlueed in any other suitable manner. Under certain conditions bituminous couorete could be rolled or suitably introduced between the adjacent edges of a road proper and the lateral portion or portions to be joined therewith as a substitute for and in place of the type and character of binding element heretofore referred to, or the bitu minous concrete could be used in conjunction with a viscous substance to forni the bindingr element between the road proper and the lateral portion or portions.

In a road constructed in accordance with the foregoing description, the disadvantages ot' prevailing roadfrouslrueliou, of the type referred to, are overcome and a road formed 'of several parallel portions is constructed in which the several portions aie bound together at their adjacent edges and :ln even, unbroken surlare presented thereby.

The invention consists l truelu i :x1 l

o .1 s i( oi arrangement wherebiy portions may be added to an existing road or one in which. a road is constriu'ied of' 'several widths ot' material and whereby thin possibility ot the materials .srparating and breaking down along their lines ot jointure is overcome,

In lhe claimsA l employ the term "row :rrete`r` in a geneiiii sense to ini-Inde a substantially hard iielestrurtible permanent roadway width without wishing lo limit all features of the invention to :i roadway width of Portland cement concrete..

I do not wish to limit my invention lo any particularmaterials. nor to any specific arrangement thereol', as it is rlear lhat various changes, lnodiicatious.` or ii'ariations may be resorted to without` departing from the spirit and scope thereof. The fundamental and basic feature of the invention eonsistin in the introduction of a binding means o? any suitable character to join and bind the adjacent poztions of the several widths of a roadway, and the speeifie disclosures hereof are of one adaptation and use to which my invention is applicable and of the specific; construction and arrangement ot' the elements thereof which the same may take.

I do not herein broadly claim the road oonstrnetion method involving that` step which tonsists in introducing a binder where the macadam and concrete widths join, nor the lmethod of repairing or piercing out old concrete roadways byV the formation of shoulders embodying bituminous or viscous binding; material and macadam or granular n'nlterial` as sneh methods are claimed in my eti-pending patent application S. No. 233,447, tiled May 9, 19i8.

What I claim is:--

l. A roadway comprising a concretey width and a parallel granular material width, the adjacent edges of the concrete and granular widths being united by interposed binding material. i

A roadway comprising a foundation, a concrete width7 a parallel loose 'material side width, and intervening binding material.

A road comprising a narrow concrete width provided with side widths formed ot :i granular fragmentary material adjacent thereto and extending laterally therefrom, said side widths diminishing in fhiekness from edges adjacent the concrete width to their outer edges, and a binding element introduced between the concrete and side widths. ,Y

4. A concrete road provided with eXtensions along its lower edge portion, fragmentary material forming widening ineansben eide said rond, intervening binding nlate'rial between said concrete road and said extensions.

A concrete road formed of a base portion and a wenring surface thereon, {raginentary material extendingr laterally 'from sind eonerete rond, and a binding element maintaining the portion of siiid material adjoining` the side edge of the concrete in position with respect to seid concrete rond.

(l, A vont-,rete road, widths on each side thereof and spaced a distance, therefrom,

and filling material interposed between said concrete rond and said widths forming a ponipaet mass therebetween. l

7. A eonerete roadway pien-ed out by a macadam or equivalent shoulder, the longi tudinal portion of the shoulder that lies p along the edge et' the concrete length boing cemented thereto,

8. A eonerete roadway piet-ed out by a macadam. or equivalent shoulder bound to the longitudinal edge thereof by n Suitable eementing binder.

9. The method of constructing roadsA which Consists in forming a cement Concrete length with a depressedlaterally-extending ltmgitudin:1l-edge portion, and' forming n shoulder of macadam or granular material :ind a suitable bituminous or viscous binder, joining the edge ot' said length and covering said portion, subst-antiall)7 as described.

l0. A roadway comprising a substantially1 hard permanentwidth, n shoulder of grannlar material, and bituminous concrete mate rial intervening between the permanent width nud said granular materiel, substantially :is described.

V1 1. A roadway comprisingr a concrete Awidth having a depressed edge "flange, n granular material slioulder,'mid bituminous concrete materiel arranged over said 'flange and intervening between the Concrete width nud the granular material.

l2. A roadway eonsieting essentially of n cement concrete length', and a parallel granular road materiel shoulder serving to widen said length and joining a longitudinal edge thereof. said :shoulder being reinforced or strengthened against breaking down from said edge.

lil. A rondway eonsistin essentially ot a, cement concrete length`r un a shoulder serv'- ing to widen said length and joining and bound to n longitudinal edge thereof, said shoulder embodying a :suitable viscous' of bituminous binding medium :ind road metal or granular material.

UURLES B. CHATFIELD.

Gti 

